The present invention relates to an improved electrical connector for electrically joining a high tension lead wire to the terminal of a spark plug and for guarding against accidental separation or looseness between the lead wire, the connector, and the spark plug.
In the past, many proposals have been made to reduce the explosion and fire hazards resulting from loose or accidentally disconnected spark plug lead wires of an internal combustion engine. These proposals include the use of electrically shielded ignition wires and spark plugs and/or specially designed dielectric shields and covers for the spark plugs. However, accidental explosions and fires caused by faulty, loose or disconnected lead wires and spark plugs continue to take place particularly with so-called stationary industrial engines which are usually surrounded by a potentially explosive atmosphere.
For example, U.S. Pat. No. 2,301,570 issued to Nowosielski describes a lead wire to a spark plug connector which comprises a female sleeve or nut member into which an insulated lead wire is fitted, with the bared, central conductor strands extending through a reduced diameter opening and into a screw-threaded counterbore, and wherein a male screw-threaded plug member having a pointed nose or end extremity is screwed into the counterbore of the female nut, so as to spread and clamp the strands of the conductor of the lead wire between the pointed end extremity and the female nut member. However, the connector disclosed by the aforesaid U.S. Pat. No. 2,301,570 makes no provision for locking the male and female connector elements together, so that engine vibrations or accidental jarring cannot loosen or separate the parts of the connector.